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sellWeak10b5-1 plan

Mike Slessor sold $2.1M of FORM

CEO at FORMFACTOR INC. 16,002 shares at an average of $130.95, traded Aug 14, 2026, filed Aug 17, 2026.

Warning score
30
Value
$2.1M
16,002 shares
Holdings after
484,204
-3% from before
From 52-week low
+373%
low $27.85, close $131.60
From 52-week high
-18%
high $159.93, as of Aug 14, 2026

Score components

  • Role
    CEO
    +25
  • Trade size
    $2.1M at market
    +25
  • Share of holdings sold
    Sold 3.2% of holdings
    0
  • Cluster
    No other insider selling within 14 days
    0
  • 10b5-1 plan
    Pre-scheduled under a 10b5-1 plan
    -20

What happened after comparable sells

Same side and tier, against the S&P 500, at 1, 3 and 6 months. Shown to Pro users; the whole table is on the backtest page.

Price around the trade, and since

From a quarter before the trade to today. The arrow is the trade, the circle the day the filing reached EDGAR, which is the first day anyone outside could act; the dotted line is the S&P 500 rebased to that day's close.

FORMOct 9, 2026 · close 139.67
Since filing Aug 17, 2026: +1.1%SPY +1.0% · excess +0.1%

Daily candles, adjusted for splits and dividends. Green arrows are insider buys, red are sells, sized by value; the dashed line is the close on the filing day, the dotted line SPY rebased to it.Charts by TradingView Lightweight Charts™

Rows in this filing

Every transaction in Form 4 0001628280-26-057485, as filed. Open on EDGAR

DateTransactionSharesPriceValueHoldings afterFiled
Aug 14, 2026SOpen-market sale
Common Stock10b5-1
-2,482$128.72$319k497,724Aug 17, 2026
Aug 14, 2026SOpen-market sale
Common Stock10b5-1
-2,892$129.55$375k494,832Aug 17, 2026
Aug 14, 2026SOpen-market sale
Common Stock10b5-1
-3,282$130.54$428k491,550Aug 17, 2026
Aug 14, 2026SOpen-market sale
Common Stock10b5-1
-1,125$131.65$148k490,425Aug 17, 2026
Aug 14, 2026SOpen-market sale
Common Stock10b5-1
-5,535$132.50$733k484,890Aug 17, 2026
Aug 14, 2026SOpen-market sale
Common Stock10b5-1
-686$133.33$91k484,204Aug 17, 2026

Related signals

Other insiders at FORMFACTOR INC and this insider’s other filings.

ScoreCompanyInsiderValueHoldingsFiled
38Weak
FORMsell 210b5-1
FORMFACTOR INC
Mike Slessor
CEO
$1.8M
17,510 shares
-4%
35Weak
FORMsell 2
FORMFACTOR INC
Kelley Steven-Waiss
director
$202k
2,100 shares
-8%
24Weak
FORMsell10b5-1
FORMFACTOR INC
Mike Slessor
CEO
$560k
4,735 shares
-1%
46Moderate
FORMsell 3
FORMFACTOR INC
Thomas St Dennis
director
$424k
2,800 shares
-9%
45Moderate
FORMsell 310b5-1
FORMFACTOR INC
Mike Slessor
CEO
$1.4M
11,890 shares
-3%
72Notable
FORMsell 5
FORMFACTOR INC
Sheri Rhodes
director
$794k
6,328 shares
-54%
58Moderate
FORMsell 7
FORMFACTOR INC
Rebeca Obregon-Jimenez
director
$484k
3,828 shares
-33%
40Moderate
FORMsell 7
FORMFACTOR INC
Thomas St Dennis
director
$116k
1,000 shares
-3%
56Moderate
FORMsell 7
FORMFACTOR INC
Brian C White
director
$410k
3,250 shares
-27%
55Moderate
FORMsell 6
FORMFACTOR INC
Kelley Steven-Waiss
director
$678k
5,400 shares
-18%

Not investment advice. Scores and forward returns are decision support built from public SEC filings and past prices; they describe what happened after comparable filings, not what will happen after this one. Do your own research and size your risk.

Mike Slessor sold $2.1M of FORM | InsiderTell